In our original announcement of the new René Herse cranks, we wrote that they were lighter than Campagnolo Record Carbon cranks. A few readers asked us to substantiate this. We weighed the cranks on Bicycle Quarterly’s precision scale (above).

We don’t have the final chainrings for our new cranks yet, so the weight may still change by a few grams, but here is the comparison:

The two cranks are not directly comparable, since the Campagnolo crank is slightly longer and has somewhat larger chainrings. However, comparing the left crankarms (which don’t have chainrings), you see that the Campagnolo arms are 62 grams (38%)heavier than the René Herse crankarms. The right arms are 59 grams heavier, indicating that chainrings and bolts weigh about the same on both cranks. (Campagnolo’s larger chainrings are thinner, and they use aluminum bolts, which makes up for their slightly larger size and greater number of bolts.)

We weighed the 2006 model, because it was the last time Campagnolo offered a separate crank without an integrated bottom bracket. Current Campagnolo cranks have integrated bottom bracket spindles. The spindles have thin walls and use very small bearings, which saves significant weight. If we include a 1950s-style René Herse bottom bracket with extra-large bearings that are pressed straight into the bottom bracket shell, the comparison is as follows:

Clearly, the low weight of modern cranks is mostly due to the superlight bottom brackets, rather than the cranks themselves. With the bottom bracket, the latest Campagnolo carbon cranks weigh 135 grams less than an equivalent set of René Herse components. Much of the Herse’s extra weight is in the large bearings (72 g for two bearings). On the plus side, the bearings last for decades without overhaul. For me, that is worth a few extra grams.

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About Jan Heine, Editor, Bicycle Quarterly

I love cycling and bicycles, especially those that take us off the beaten path. I edit Bicycle Quarterly magazine, and occasionally write for other publications. One of our companies, Bicycle Quarterly Press publishes cycling books, while Compass Bicycles Ltd. makes and distributes high-quality bicycle components for real-world riders.

Jan,
The Herse cranks are just right. Thank you for bringing us practicle and beautiful bicycle components.
Modern Campagnolo bottom brackets, with their very small bearings, have a reputation of wearing out quickly. I was curious enough to take one apart after removing, and the bearings are surprisingly small. Its short life is not a surprise. It was replaced by a Phil Wood after learning SKF did not make the size we sought.

I agree that obsessing about weight isn’t useful once the bike is built. However, riding a light bike has a joy that is hard to replicate with a heavier machine. When I specify parts, I try to make sure they don’t carry excess weight, but without compromising function or reliability. Then I know that my bike is as light as it can be within reason, and stop thinking about the weight for the rest of that bike’s life.

The TA crank is ten grams heavier, and the longer bb is 20g heavier. But that 30g weight savings isn’t really the point of the crank.

The René Herse design is just more user-friendly. The rings are stiffer and don’t have a hole drilled through the thin part of the web of the big ring (I’ve seen a modern TA ring fail there on two occasions, though not on my machines, thankfully), the chainring bolts aren’t semi-disposable, the RH crank uses standard tools, it uses modern standard steel chainring bolts (the stupidly aluminum TA crank-to-outer chainring nuts crack as we’ve discussed), and you don’t have to fidget with the front derailleur cage to make it shift right and clear the crank (8.3mm between the outer ring and the inner edge of the drive side arm, which is a bit more than a Shimano 7700 crank). It has a potentially wider range of chainring choices than the TA (subject to what René Herse and Compass Bicycle will be producing) and, with a 110mm JIS bottom bracket, anyway, has a reasonably narrow tread width. And it is as light as any aluminum crank made.

The Super Record is a bit lighter than the Record… and a lot more expensive. I can tell you already that the Herse cranks, even with an SKF bottom bracket, will be much less expensive than the equivalent Campagnolo Record (much less Super Record) parts.

I think the idea of offering a crank like the R. Herse is great, especially with the range of gears that it will allow. I know that there’s something to be said for keeping a classical look, but I also think that if you can improve a product, why not? for instance, What if the R. Herse cranks arms used the outboard bearings? and since the bottom brackets use smaller bearings then desireable, make an outboad bottom bracket with larger bearings? it seems like the product would then weigh less with a relatively simple change while not sacrifice durability.

I agree that it makes sense to improve where improvements are possible. However, outboard bearings don’t seem to be an improvement. Basically, component makers decided they wanted bigger bottom bracket shells, so they screwed extensions into the frame’s BB shell. These extensions aren’t aligned very well, because the facing of the frame with hand tools is always less than accurate. So you have poorly aligned frame extensions into which you install your bottom bracket. The larger BB shell allowed the makers to use larger-diameter spindles to save weight, but bearing life is severely compromised.

A more logical approach is BB30, which just makes the BB shell larger from the beginning. However, I don’t think standard BB shells are undersized, if the bottom bracket is designed well. Only when you use a separate cartridge with pressed-in bearings (most cartridge BBs), then you run out of room and have to use small bearings. When you either run the bearings directly on the outer sleeve and the spindle of the cartridge (as does SKF) or press the bearings straight into the frame (BB30, old Herse/Singer custom BBs), then you can use bearings that are more than large enough.

If you want to use a larger spindle, then you really can’t do a square taper any longer. Basically, the tapers have to be pretty solid, so you don’t crush them as you tighten the crank. (The advantage of the larger spindles lies in their very thin walls.) ISIS tried to get around this with a “hard stop” on the spindle, but this means that the “self-restoring” capabilities of the crank taper as it wears no longer exist. Basically, your crank eventually comes loose and then that’s it. Plus, ISIS BBs aren’t common any longer, and the only one that works well is SKF (large spindle in standard BB shell is a problem for most makers). I don’t see a good way around this – ISIS with BB30 might have worked better, but it would mean introducing a new standard that fits only few bikes, all for questionable benefits.

We are currently testing a bike with BB30, and it seems to be fine. Is it better than a standard bottom bracket? I can’t detect a difference… I like the idea of pressing the bearings straight into the frame – my Singer has that system, and it’s lasted well for 37 years with only one bearing replacement. However, most BB30 use an even larger spindle instead of larger bearings, so I doubt they’ll last as long.

By the way, will it be possible to use the “new” René Herse cranks with the “old” Renée Herse chainrings? The aim is to use clipless pedals on a vintage René Herse bicycle: I must admit that I have no problem with steel frame, shifters on the down tube, etc. BUT I dislike “classic” pedals :-(((

René Herse chainrings changed quite a bit over the years, but the last chainrings from the 1970s onwards will work with the new cranks. The new rings will have thinner teeth to work with 10-speed chains, and optimized tooth profiles for longer wear and better shifting, but otherwise, they are very similar.

Note that if you use the new cranks, you need a new bottom bracket spindle, as the slightly curved arms require a spindle that is almost 10 mm shorter.